The **HTS-1D-R** is a specialized high-temperature humidity and temperature sensor probe, typically used in industrial environmental chambers and control systems. It is designed to interface with transmitters or controllers to provide precise environmental monitoring in harsh conditions. --- ### 1. Key Technical Specifications The electronics of the HTS-1D-R are optimized for stability and linear output across a wide range of temperatures. | Feature | Specification | | :--- | :--- | | **Sensing Element** | Capacitive Polymer (Humidity) / Pt100 or Pt1000 (Temperature) | | **Humidity Range** | 0% to 100% RH | | **Operating Temp (Probe)** | -40°C to +180°C (High-temp variant) | | **Output Signal** | Digital (RS485/Modbus) or Analog (0-1V / 4-20mA via transmitter) | | **Accuracy** | ±1.5% to 2% RH / ±0.2°C Temperature | --- ### 2. Core Electronic Components The internal architecture of the probe consists of several critical stages: #### A. The Sensing Head * **Capacitive Humidity Sensor:** Consists of a dielectric polymer layer between two electrodes. As water vapor is absorbed, the capacitance changes proportionally to the relative humidity. * **RTD (Resistance Temperature Detector):** Usually a **Pt100** element that changes resistance based on temperature, providing high linearity and long-term stability compared to thermistors. #### B. Signal Conditioning Circuitry Because the raw signal from a capacitive sensor is very small (picofarads), the internal electronics include: 1. **C/D Converter:** Converts capacitance change into a digital signal or frequency. 2. **Microprocessor:** Applies calibration coefficients stored in the non-volatile memory to correct for sensor drift and temperature dependency. 3. **Filtering:** Integrated RC filters or digital low-pass filters to reduce EMI (Electromagnetic Interference) common in industrial settings. #### C. Connectivity & Protection * **Stainless Steel Housing:** Acts as a Faraday cage to protect internal electronics from static and RF interference. * **Sintered Filter:** A porous metal cap that protects the electronic sensing elements from dust and high-velocity airflow while allowing water vapor to pass through. --- ### 3. Connection Pinout (Typical) Most HTS series probes use a circular industrial connector (like M12). The typical wiring configuration is: | Pin | Function | Description | | :--- | :--- | :--- | | **1** | V+ | Power Supply (usually 12-24V DC) | | **2** | GND | Ground / Common | | **3** | RS485 A / Signal | Communication or Analog Output 1 | | **4** | RS485 B / Signal | Communication or Analog Output 2 | --- ### 4. Application Integration The HTS-1D-R is rarely used as a standalone component. It is usually integrated into a larger system via: * **PLC Integration:** Connecting the RS485 lines to a Programmable Logic Controller via Modbus RTU. * **Transmitter Units:** Connecting to a wall-mounted display unit (like the EE310 or similar series) that converts the probe signal into a standard 4-20mA loop.